package com.sky.service.impl;

import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
import com.sky.constant.MessageConstant;
import com.sky.constant.StatusConstant;
import com.sky.dto.SetmealDTO;
import com.sky.dto.SetmealPageQueryDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.SetmealDish;
import com.sky.exception.DeletionNotAllowedException;
import com.sky.exception.SetmealEnableFailedException;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealDishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.result.PageResult;
import com.sky.service.SetmealService;
import com.sky.vo.DishItemVO;
import com.sky.vo.SetmealVO;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

/**
 * 套餐业务实现
 */
@Service
@Slf4j
public class SetmealServiceImpl implements SetmealService {

    @Autowired
    private SetmealMapper setmealMapper;
    @Autowired
    private SetmealDishMapper setmealDishMapper;
    @Autowired
    private DishMapper dishMapper;

    /**
     * 根据分类id查询套餐
     * @param setmeal
     * @return
     */
    public List<Setmeal> list(Setmeal setmeal) {
        List<Setmeal> list = setmealMapper.list(setmeal);
        return list;
    }

    /**
     * 根据id查询菜品选项
     * @param id
     * @return
     */
    public List<DishItemVO> getDishItemById(Long id) {
        return setmealMapper.getDishItemBySetmealId(id);
    }

    /**
     * 新增套餐，同时需要保存套餐和菜品的关联关系
     * 涉及两个数据库表的操作，开启事务注解
     * @param setmealDTO
     */
    @Transactional
    public void saveWithDish(SetmealDTO setmealDTO) {
        Setmeal setmeal = new Setmeal();
        BeanUtils.copyProperties(setmealDTO, setmeal);// 属性拷贝

        // 向套餐表插入数据
        setmealMapper.insert(setmeal);

        // 获取生成的套餐id
        Long setmealId = setmeal.getId();

        List<SetmealDish> setmealDishes = setmealDTO.getSetmealDishes();// 获取这个套餐包含的菜品集合
        setmealDishes.forEach(setmealDish -> {
            setmealDish.setSetmealId(setmealId);// 设置关联表的套餐id
        });

        // 保存套餐和菜品的关联关系
        setmealDishMapper.insertBatch(setmealDishes);
    }

    /**
     * 套餐分页查询
     * @param setmealPageQueryDTO
     * @return
     */
    public PageResult pageQuery(SetmealPageQueryDTO setmealPageQueryDTO) {

        // 分页查询
        PageHelper.startPage(setmealPageQueryDTO.getPage(), setmealPageQueryDTO.getPageSize());

        Page<SetmealVO> page = setmealMapper.pageQuery(setmealPageQueryDTO);

        long total = page.getTotal();// 获取总记录数
        List<SetmealVO> records = page.getResult();// 获取当页数据
        return new PageResult(total, records);// 封装到统一返回对象PageResult
    }

    /**
     * 根据id批量删除套餐
     * @param ids
     */
    @Transactional
    public void deleteBatch(List<Long> ids) {

        // 判断套餐的状态是否为起售
        for (Long id : ids) {
            if (Objects.equals(setmealMapper.getById(id).getStatus(), StatusConstant.ENABLE)) {
                // 起售中的套餐不能删除
                throw new DeletionNotAllowedException(MessageConstant.SETMEAL_ON_SALE);
            }
        }
        // 删除套餐表中的数据
        setmealMapper.deleteByIds(ids);

        // 删除套餐对应的关系表数据
        setmealDishMapper.deleteBySetmealId(ids);
    }

    /**
     * 根据id查询套餐和套餐菜品关系
     * @param id
     * @return
     */
    public SetmealVO getByIdWithDish(Long id) {

        SetmealVO setmealVO = new SetmealVO();
        // 根据套餐id查询套餐
        Setmeal setmeal = setmealMapper.getById(id);
        BeanUtils.copyProperties(setmeal, setmealVO);// 属性拷贝

        // 根据套餐id查询套餐菜品关系表
        List<SetmealDish> setmealDishes = setmealDishMapper.getBySetmealId(id);
        setmealVO.setSetmealDishes(setmealDishes);
        return setmealVO;
    }

    /**
     * 修改套餐
     * 涉及了套餐表和套餐菜品关系表，需要开启事务
     * @param setmealDTO
     */
    @Transactional
    public void update(SetmealDTO setmealDTO) {
        Setmeal setmeal = new Setmeal();
        BeanUtils.copyProperties(setmealDTO, setmeal);

        // 1、修改套餐表，执行update
        setmealMapper.update(setmeal);

        // 套餐id
        Long setmealId = setmealDTO.getId();
        List<Long> setmealIds = new ArrayList<>();
        setmealIds.add(setmealId);

        // 2、删除套餐和菜品的关联关系，操作setmeal_dish表，执行delete
        setmealDishMapper.deleteBySetmealId(setmealIds);

        List<SetmealDish> setmealDishes = setmealDTO.getSetmealDishes();// 获取菜品集合
        setmealDishes.forEach(setmealDish -> {
            setmealDish.setSetmealId(setmealId);
        });

        // 3、重新插入套餐和菜品的关联关系，操作setmeal_dish表，执行insert
        setmealDishMapper.insertBatch(setmealDishes);
    }

    /**
     * 修改套餐起售状态
     * @param status
     * @param id
     */
    public void startOrStop(Integer status, Long id) {
        // 起售套餐时，判断套餐内是否有停售菜品，有停售菜品提示“套餐内包含位起售菜品，无法起售”
        if (Objects.equals(status, StatusConstant.ENABLE)) {
            List<Dish> dishList = dishMapper.getBySetmealId(id);
            if (dishList != null && !dishList.isEmpty()) {
                dishList.forEach(dish -> {
                    if (StatusConstant.DISABLE.equals(dish.getStatus())) {
                        throw new SetmealEnableFailedException(MessageConstant.SETMEAL_ENABLE_FAILED);
                    }
                });
            }
        }

        // 更改菜品状态
        Setmeal setmeal = Setmeal.builder()
                .id(id)
                .status(status)
                .build();
        setmealMapper.update(setmeal);// 调用更新方法
    }
}
